Q. Does a term following the word “called” need to be in italics or quotation marks—or neither? For example, “a series of bends called meanders.”
A. CMOS takes a relatively hands-off approach to terms introduced by called, known as, referred to as, and the like. The idea is that these are simply extensions of the linking verb to be:
Those are potatoes.
or, more specifically,
Those are called potatoes.
But if you want to draw attention to such a term for any reason, you can use italics (or quotation marks). CMOS does this, for example, in certain passages in chapter 5 where we wanted to emphasize grammar-related vocabulary—as in the following sentence from CMOS 5.180:
A phrasal preposition, sometimes called a complex preposition, is two or more separate words used as a prepositional unit.
For the related issue of what to do following so-called (where quotation marks are considered unnecessary in Chicago style), see CMOS 7.62.